20 April 2016

HOW TO KNOW IF YOUR INFRA-RED REMOTE CONTROL IS WORKING!

Your TV, air conditioner, fan or stereo system is not responding to presses of your remote control. You replace the batteries in your infra-red remote control but it makes no difference. So how to know if the problem is with the remote control or the appliance you are trying to remotely control with it, especially when our eyes cannot see infra-red light?

Try it, just press a button on your remote control whilst looking at the infra-red LED and see if you can see it flashing. 

Not to get too technical, infra-red light comprises of frequencies lower than the red end of the visible spectrum or that very narrow range of frequencies of electromagnetic waves which our eyes can see - i.e. frequencies ranging from 405 THz to 790 THz (Terahertz). Above 790 THz is ultra violet (UV) light which our eyes cannot see either.

Anyway, I learned how to see the infra-red LED flashing last Wednesday - i.e. 13th of April 2016, when I took my aunt's suspected faulty TV remote control into the Philips service centre on Jalan Kilang, Petaling Jaya.

I asked the customer service person whether he could test the remote out with a TV but instead he took out his smartphone and viewed the remote through its display screen and said "it's not working". He then did the same with the replacement remote for which Philips charged RM50 and confirmed that it is working.

"Are you running any special application on your phone", I asked and he replied, "No. I just viewed it through the phone's camera. It works with most phones, your's too, except for the iPhone 6". So I took out my Nokia, turned on the camera, held the replacement remote below it, pressed a button on the remote and low and behold, I saw the infra-red LED blinking.

CLICK HERE TO SEE INFRA-RED LED BLINKING

"Why doesn't it work with the iPhone 6", I asked and he replied, "Well, it of more sophisticated".

He then advised me not to use expensive alkaline cells with the remote but instead regular use cheaper heavy duty zinc-manganese cells.

Much earlier, I had been given similar advice with regards digital clocks and according to Michael Bluejay's Battery Guide, digital clocks and remote controls draw low current from the battery.

http://michaelbluejay.com/batteries/

So I paid him the RM50, he gave me the receipt, I thanked him and since this replacement remote control, even from Philips, comes with no warranty but though I could return it for a free exchange within the same day, if it was not working, so I rushed off to my aunt's place that very morning to test it with her TV and yes it worked fine - Yippiee! So I left it there.

When I got home, I tried viewing the infra-red LEDs of several remote controls in my home through my phone's camera and yes, I could see them blinking. Whilst I have not tried it with a dedicated digital camera, perhaps you may want to experiment.

Now why cannot a iPhone 6 be used to view a blinking infra-red LED. What did he mean by this model being "more sophisticated".

Well, I don't have an iPhone 6 to verify his claim but it makes sense that if a camera is to produce a picture which faithfully reproduce what our eyes see, then the camera's visible spectrum must as closely as possible match our eyes' visible spectrum, otherwise pictures it takes will contain more than our eyes actually see, so I guess that being "more sophisticated", as this customer service person described, the range of an iPhone 6 camera's photo sensor closely matches our visible spectrum or its processing circuitry more tightly filters out frequencies outside our visible spectrum.   

Once again, I've not had the opportunity to try this out but anyone with an iPhone 6 is welcome to try out for themselves.

"Now what actually happened to the remote?" you wonder.

Well my aunt accidentally spilled some wine onto the remote which was on the same side table and she immediately shook off any excess wine on the remote and wiped it clean and since it continued to work for a whole afterwards, she thought that all was OK with the remote until it later died on her.

Now in such situations, with a remote control, mobile phone, digital camera or any other battery powered device, remove the batteries as soon to avoid the short circuiting of any delicate electronics within.

After removing the batteries, SIM and any memory cards as in the case of a mobile phone, try and dismantle the device as best you can, such as remove the front and back covers if possible.

Then rinse the remote or phone in clean water, shaking it in the water to ensure that any acids, salts, alkalis or whatever in the fluid which has got into the device is washed out.

Shake the device vigourously to expel as much water inside as you can, then suck out whatever remaining water with a powerful vacuum cleaner.

Then leave the device standing upright ideally for a day, two or even three days in a warm and dry place so than any moisture left in it will evaporate.

Once you are satisfied that it has properly dried out, re-assemble the device, put in the batteries and test it out.

I first brought my aunt's remote home and cleaned it up as described but it appears that it was too late and the wine with the acids and other substances it contains had resulted in the remote's electronics shorting out which killed it.

Meanwhile, why not have some fun viewing the blinking infra-red LED on your remote control through your digital camera's of phone camera's viewfinder.

Cheers

Charles F. Moreira